Genetics research has grown in leaps and bounds over the last half-century. Research into the chromosome 22q11.2 deletion has been lengthy and painstaking, but scientists and doctors are constantly learning more about it.
Here's an overview of what we've learned so far:
1965 Angelo DiGeorge, MD, an endocrinologist at St. Christopher's Hospital for Children, first describes children with calcium problems and trouble with infection. Later, congenital heart problems are added, and the triad known as DiGeorge syndrome is born.
1968 William Strong, MD, a physician from Cleveland, reports heart abnormalities, learning differences and a characteristic facial appearance in four members of one family.
1976 Dr. Kinouchi, a Japanese physician, reports a typical facial appearance specifically seen in patients with heart problems (called conotruncal anomalies) and calls it conotruncal anomaly facial syndrome (CTAF).
1978 Robert Shprintzen, PhD, a speech pathologist in New York, describes a disorder running in families. Patients have a combination of cleft palate or velopharyngeal incompetence, heart defects, learning disabilities and a characteristic facial appearance. He calls it velocardiofacial syndrome (VCFS).
1980 Japanese physician Dr. Shimizu notices similiarities between patients who were diagnosed with CTAF and those with DiGeorge syndrome.
1981 Dr. Shprintzen reviews patients reported to have CTAF and suggests they have VCFS.
1981/1982 French physician Dr. de la Chappelle, as well as Richard Kelley, MD, PhD, Elaine Zackai, MD, and Beverly Emanuel, PhD (all at The Children's Hospital of Philadelphia), find that patients with DiGeorge syndrome have a rearrangement of chromosome 22 that caused them to be missing a very small piece of chromosomal material on the long arm (q11.2).
1990 Utah physician C.A. Stevens, MD, reports a patient with DiGeorge syndrome whose father had a cleft palate, problems fighting infection, and facial features consistent with VCFS. Several other physicians report similar findings.
1992 Deborah A. Driscoll, MD (at The Children's Hospital of Philadelphia) demonstrates that the vast majority of patients with VCFS had a chromosome 22q11.2 deletion. She finds this deletion no different from that seen in patients with DiGeorge syndrome. This supports the theory that these are, in fact, the same syndrome.
1994 Dr. Gianotti from Italy suggests that Cayler Cardiofacial syndrome, also known as asymmetric crying facies, is due to a 22q11.2 deletion.
1995 Donna M. McDonald-McGinn, MS, CGC (at Children's Hospital) suggests that some cases of the autosomal dominant form of Opitz G/BBB syndrome — a diagnosis that includes cleft lip and palate, laryngotracheoesophageal abnormalities, hypospadias, and hypertelorism — are due to the 22q11.2 deletion.
1996 LaCassie and Arriaza report additional patients with Opitz G/BBB syndrome and the 22q11.2 deletion.